A study finds that drinking generally has no major negative effects on young adults' earnings. Data from the 1979-90 panels of the National Longitudinal Survey of Youth were obtained for roughly 900 pairs of young people and a same-gender sibling. The NLSY contains detailed information on over 12,000 individuals who were 14 to 21 years old in 1979. Annual data are available for each individual in the survey, and retention through the 1990 panel is about 90 percent. Least squares estimates reveal that young men's earnings fall with drinking, while young women's earnings rise with moderate and heavy drinking. These effects are not statistically significant in longitudinal and sibling estimates, however. Instrumental variable estimates show much larger negative effects of drinking on male earnings, but alcohol consumption seems to increase female hours of work and sometimes raises earnings substantially. A variety of other findings are presented. Comments and discussion by P.J. Cook and Sam Peltzman follow.